Harmonise use of EVP_CTRL_GET_TAG/EVP_CTRL_SET_TAG/EVP_CTRL_SET_IVLEN

[openssl.git] / doc / crypto / EVP_EncryptInit.pod

diff --git a/doc/crypto/EVP_EncryptInit.pod b/doc/crypto/EVP_EncryptInit.pod
index 3b132c4490cc53fbf59476fde162ebbac592abb7..6d897dab35c18f51d087ab3896eaf951ae9165d2 100644 (file)
--- a/doc/crypto/EVP_EncryptInit.pod
+++ b/doc/crypto/EVP_EncryptInit.pod
@@ -20,13 +20,16 @@ EVP_CIPHER_CTX_set_padding,  EVP_enc_null, EVP_des_cbc, EVP_des_ecb,
 EVP_des_cfb, EVP_des_ofb, EVP_des_ede_cbc, EVP_des_ede, EVP_des_ede_ofb,
 EVP_des_ede_cfb, EVP_des_ede3_cbc, EVP_des_ede3, EVP_des_ede3_ofb,
 EVP_des_ede3_cfb, EVP_desx_cbc, EVP_rc4, EVP_rc4_40, EVP_idea_cbc,
 EVP_des_cfb, EVP_des_ofb, EVP_des_ede_cbc, EVP_des_ede, EVP_des_ede_ofb,
 EVP_des_ede_cfb, EVP_des_ede3_cbc, EVP_des_ede3, EVP_des_ede3_ofb,
 EVP_des_ede3_cfb, EVP_desx_cbc, EVP_rc4, EVP_rc4_40, EVP_idea_cbc,

-EVP_idea_ecb, EVP_idea_cfb, EVP_idea_ofb, EVP_idea_cbc, EVP_rc2_cbc,
+EVP_idea_ecb, EVP_idea_cfb, EVP_idea_ofb, EVP_rc2_cbc,

 EVP_rc2_ecb, EVP_rc2_cfb, EVP_rc2_ofb, EVP_rc2_40_cbc, EVP_rc2_64_cbc,
 EVP_bf_cbc, EVP_bf_ecb, EVP_bf_cfb, EVP_bf_ofb, EVP_cast5_cbc,
 EVP_cast5_ecb, EVP_cast5_cfb, EVP_cast5_ofb, EVP_rc5_32_12_16_cbc,
 EVP_rc2_ecb, EVP_rc2_cfb, EVP_rc2_ofb, EVP_rc2_40_cbc, EVP_rc2_64_cbc,
 EVP_bf_cbc, EVP_bf_ecb, EVP_bf_cfb, EVP_bf_ofb, EVP_cast5_cbc,
 EVP_cast5_ecb, EVP_cast5_cfb, EVP_cast5_ofb, EVP_rc5_32_12_16_cbc,

-EVP_rc5_32_12_16_ecb, EVP_rc5_32_12_16_cfb, EVP_rc5_32_12_16_ofb, 
-EVP_aes_128_gcm, EVP_aes_192_gcm, EVP_aes_256_gcm, EVP_aes_128_ccm,
-EVP_aes_192_ccm, EVP_aes_256_ccm - EVP cipher routines
+EVP_rc5_32_12_16_ecb, EVP_rc5_32_12_16_cfb, EVP_rc5_32_12_16_ofb,
+EVP_aes_128_cbc, EVP_aes_128_ecb, EVP_aes_128_cfb, EVP_aes_128_ofb,
+EVP_aes_192_cbc, EVP_aes_192_ecb, EVP_aes_192_cfb, EVP_aes_192_ofb,
+EVP_aes_256_cbc, EVP_aes_256_ecb, EVP_aes_256_cfb, EVP_aes_256_ofb,
+EVP_aes_128_gcm, EVP_aes_192_gcm, EVP_aes_256_gcm,
+EVP_aes_128_ccm, EVP_aes_192_ccm, EVP_aes_256_ccm - EVP cipher routines

 
 =head1 SYNOPSIS
 
 
 =head1 SYNOPSIS
 


@@ -125,12 +128,13 @@ writes the encrypted version to B<out>. This function can be called
 multiple times to encrypt successive blocks of data. The amount
 of data written depends on the block alignment of the encrypted data:
 as a result the amount of data written may be anything from zero bytes
 multiple times to encrypt successive blocks of data. The amount
 of data written depends on the block alignment of the encrypted data:
 as a result the amount of data written may be anything from zero bytes

-to (inl + cipher_block_size - 1) so B<outl> should contain sufficient
+to (inl + cipher_block_size - 1) so B<out> should contain sufficient

 room. The actual number of bytes written is placed in B<outl>.
 
 If padding is enabled (the default) then EVP_EncryptFinal_ex() encrypts
 the "final" data, that is any data that remains in a partial block.
 room. The actual number of bytes written is placed in B<outl>.
 
 If padding is enabled (the default) then EVP_EncryptFinal_ex() encrypts
 the "final" data, that is any data that remains in a partial block.

-It uses L<standard block padding|/NOTES> (aka PKCS padding). The encrypted
+It uses standard block padding (aka PKCS padding) as described in
+the NOTES section, below. The encrypted

 final data is written to B<out> which should have sufficient space for
 one cipher block. The number of bytes written is placed in B<outl>. After
 this function is called the encryption operation is finished and no further
 final data is written to B<out> which should have sufficient space for
 one cipher block. The number of bytes written is placed in B<outl>. After
 this function is called the encryption operation is finished and no further


@@ -138,7 +142,7 @@ calls to EVP_EncryptUpdate() should be made.
 
 If padding is disabled then EVP_EncryptFinal_ex() will not encrypt any more
 data and it will return an error if any data remains in a partial block:
 
 If padding is disabled then EVP_EncryptFinal_ex() will not encrypt any more
 data and it will return an error if any data remains in a partial block:

-that is if the total data length is not a multiple of the block size. 
+that is if the total data length is not a multiple of the block size.

 
 EVP_DecryptInit_ex(), EVP_DecryptUpdate() and EVP_DecryptFinal_ex() are the
 corresponding decryption operations. EVP_DecryptFinal() will return an
 
 EVP_DecryptInit_ex(), EVP_DecryptUpdate() and EVP_DecryptFinal_ex() are the
 corresponding decryption operations. EVP_DecryptFinal() will return an


@@ -161,7 +165,7 @@ after all operations using a cipher are complete so sensitive information
 does not remain in memory.
 
 EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a
 does not remain in memory.
 
 EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a

-similar way to EVP_EncryptInit_ex(), EVP_DecryptInit_ex and
+similar way to EVP_EncryptInit_ex(), EVP_DecryptInit_ex() and

 EVP_CipherInit_ex() except the B<ctx> parameter does not need to be
 initialized and they always use the default cipher implementation.
 
 EVP_CipherInit_ex() except the B<ctx> parameter does not need to be
 initialized and they always use the default cipher implementation.
 


@@ -278,7 +282,7 @@ OBJECT IDENTIFIER or NID_undef if it has no defined OBJECT IDENTIFIER.
 
 EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure.
 
 
 EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure.
 

-EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for 
+EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for

 success or zero for failure.
 
 =head1 CIPHER LISTING
 success or zero for failure.
 
 =head1 CIPHER LISTING


@@ -291,70 +295,89 @@ All algorithms have a fixed key length unless otherwise stated.
 
 Null cipher: does nothing.
 
 
 Null cipher: does nothing.
 

-=item EVP_des_cbc(void), EVP_des_ecb(void), EVP_des_cfb(void), EVP_des_ofb(void)
+=item EVP_aes_128_cbc(), EVP_aes_128_ecb(), EVP_aes_128_cfb(), EVP_aes_128_ofb()

 
 

-DES in CBC, ECB, CFB and OFB modes respectively. 
+AES with a 128-bit key in CBC, ECB, CFB and OFB modes respectively.

 
 

-=item EVP_des_ede_cbc(void), EVP_des_ede(), EVP_des_ede_ofb(void),  EVP_des_ede_cfb(void)
+=item EVP_aes_192_cbc(), EVP_aes_192_ecb(), EVP_aes_192_cfb(), EVP_aes_192_ofb()
+
+AES with a 192-bit key in CBC, ECB, CFB and OFB modes respectively.
+
+=item EVP_aes_256_cbc(), EVP_aes_256_ecb(), EVP_aes_256_cfb(), EVP_aes_256_ofb()
+
+AES with a 256-bit key in CBC, ECB, CFB and OFB modes respectively.
+
+=item EVP_des_cbc(), EVP_des_ecb(), EVP_des_cfb(), EVP_des_ofb()
+
+DES in CBC, ECB, CFB and OFB modes respectively.
+
+=item EVP_des_ede_cbc(), EVP_des_ede(), EVP_des_ede_ofb(),  EVP_des_ede_cfb()

 
 Two key triple DES in CBC, ECB, CFB and OFB modes respectively.
 
 
 Two key triple DES in CBC, ECB, CFB and OFB modes respectively.
 

-=item EVP_des_ede3_cbc(void), EVP_des_ede3(), EVP_des_ede3_ofb(void),  EVP_des_ede3_cfb(void)
+=item EVP_des_ede3_cbc(), EVP_des_ede3(), EVP_des_ede3_ofb(),  EVP_des_ede3_cfb()

 
 Three key triple DES in CBC, ECB, CFB and OFB modes respectively.
 
 
 Three key triple DES in CBC, ECB, CFB and OFB modes respectively.
 

-=item EVP_desx_cbc(void)
+=item EVP_desx_cbc()

 
 DESX algorithm in CBC mode.
 
 
 DESX algorithm in CBC mode.
 

-=item EVP_rc4(void)
+=item EVP_rc4()

 
 RC4 stream cipher. This is a variable key length cipher with default key length 128 bits.
 
 
 RC4 stream cipher. This is a variable key length cipher with default key length 128 bits.
 

-=item EVP_rc4_40(void)
+=item EVP_rc4_40()

 
 

-RC4 stream cipher with 40 bit key length. This is obsolete and new code should use EVP_rc4()
+RC4 stream cipher with 40 bit key length.
+This is obsolete and new code should use EVP_rc4()

 and the EVP_CIPHER_CTX_set_key_length() function.
 
 and the EVP_CIPHER_CTX_set_key_length() function.
 

-=item EVP_idea_cbc() EVP_idea_ecb(void), EVP_idea_cfb(void), EVP_idea_ofb(void), EVP_idea_cbc(void)
+=item EVP_idea_cbc() EVP_idea_ecb(), EVP_idea_cfb(), EVP_idea_ofb()

 
 IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respectively.
 
 
 IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respectively.
 

-=item EVP_rc2_cbc(void), EVP_rc2_ecb(void), EVP_rc2_cfb(void), EVP_rc2_ofb(void)
+=item EVP_rc2_cbc(), EVP_rc2_ecb(), EVP_rc2_cfb(), EVP_rc2_ofb()

 
 RC2 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
 length cipher with an additional parameter called "effective key bits" or "effective key length".
 By default both are set to 128 bits.
 
 
 RC2 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
 length cipher with an additional parameter called "effective key bits" or "effective key length".
 By default both are set to 128 bits.
 

-=item EVP_rc2_40_cbc(void), EVP_rc2_64_cbc(void)
+=item EVP_rc2_40_cbc(), EVP_rc2_64_cbc()

 
 RC2 algorithm in CBC mode with a default key length and effective key length of 40 and 64 bits.
 These are obsolete and new code should use EVP_rc2_cbc(), EVP_CIPHER_CTX_set_key_length() and
 EVP_CIPHER_CTX_ctrl() to set the key length and effective key length.
 
 
 RC2 algorithm in CBC mode with a default key length and effective key length of 40 and 64 bits.
 These are obsolete and new code should use EVP_rc2_cbc(), EVP_CIPHER_CTX_set_key_length() and
 EVP_CIPHER_CTX_ctrl() to set the key length and effective key length.
 

-=item EVP_bf_cbc(void), EVP_bf_ecb(void), EVP_bf_cfb(void), EVP_bf_ofb(void);
+=item EVP_bf_cbc(), EVP_bf_ecb(), EVP_bf_cfb(), EVP_bf_ofb()

 
 Blowfish encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
 length cipher.
 
 
 Blowfish encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
 length cipher.
 

-=item EVP_cast5_cbc(void), EVP_cast5_ecb(void), EVP_cast5_cfb(void), EVP_cast5_ofb(void)
+=item EVP_cast5_cbc(), EVP_cast5_ecb(), EVP_cast5_cfb(), EVP_cast5_ofb()

 
 CAST encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
 length cipher.
 
 
 CAST encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key
 length cipher.
 

-=item EVP_rc5_32_12_16_cbc(void), EVP_rc5_32_12_16_ecb(void), EVP_rc5_32_12_16_cfb(void), EVP_rc5_32_12_16_ofb(void)
+=item EVP_rc5_32_12_16_cbc(), EVP_rc5_32_12_16_ecb(), EVP_rc5_32_12_16_cfb(), EVP_rc5_32_12_16_ofb()

 
 RC5 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key length
 cipher with an additional "number of rounds" parameter. By default the key length is set to 128
 bits and 12 rounds.
 
 
 RC5 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key length
 cipher with an additional "number of rounds" parameter. By default the key length is set to 128
 bits and 12 rounds.
 

-=item EVP_aes_128_gcm(void), EVP_aes_192_gcm(void), EVP_aes_256_gcm(void)
+=item EVP_aes_128_gcm(), EVP_aes_192_gcm(), EVP_aes_256_gcm()

 
 AES Galois Counter Mode (GCM) for 128, 192 and 256 bit keys respectively.
 These ciphers require additional control operations to function correctly: see
 
 AES Galois Counter Mode (GCM) for 128, 192 and 256 bit keys respectively.
 These ciphers require additional control operations to function correctly: see

-L<GCM mode> section below for details.
+the L<GCM and OCB modes> section below for details.

 
 

-=item EVP_aes_128_ccm(void), EVP_aes_192_ccm(void), EVP_aes_256_ccm(void)
+=item EVP_aes_128_ocb(void), EVP_aes_192_ocb(void), EVP_aes_256_ocb(void)
+
+Offest Codebook Mode (OCB) for 128, 192 and 256 bit keys respectively.
+These ciphers require additional control operations to function correctly: see
+the L<GCM and OCB modes> section below for details.
+
+=item EVP_aes_128_ccm(), EVP_aes_192_ccm(), EVP_aes_256_ccm()

 
 AES Counter with CBC-MAC Mode (CCM) for 128, 192 and 256 bit keys respectively.
 These ciphers require additional control operations to function correctly: see
 
 AES Counter with CBC-MAC Mode (CCM) for 128, 192 and 256 bit keys respectively.
 These ciphers require additional control operations to function correctly: see


@@ -362,13 +385,13 @@ CCM mode section below for details.
 
 =back
 
 
 =back
 

-=head1 GCM Mode
+=head1 GCM and OCB Modes

 
 

-For GCM mode ciphers the behaviour of the EVP interface is subtly altered and
-several GCM specific ctrl operations are supported.
+For GCM and OCB mode ciphers the behaviour of the EVP interface is subtly
+altered and several additional ctrl operations are supported.

 
 To specify any additional authenticated data (AAD) a call to EVP_CipherUpdate(),
 
 To specify any additional authenticated data (AAD) a call to EVP_CipherUpdate(),

-EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made with the output 
+EVP_EncryptUpdate() or EVP_DecryptUpdate() should be made with the output

 parameter B<out> set to B<NULL>.
 
 When decrypting the return value of EVP_DecryptFinal() or EVP_CipherFinal()
 parameter B<out> set to B<NULL>.
 
 When decrypting the return value of EVP_DecryptFinal() or EVP_CipherFinal()


@@ -376,42 +399,50 @@ indicates if the operation was successful. If it does not indicate success
 the authentication operation has failed and any output data B<MUST NOT>
 be used as it is corrupted.
 
 the authentication operation has failed and any output data B<MUST NOT>
 be used as it is corrupted.
 

-The following ctrls are supported in GCM mode:
+The following ctrls are supported in both GCM and OCB modes:
+
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL);

 
 

- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, ivlen, NULL);
+Sets the IV length: this call can only be made before specifying an IV. If
+not called a default IV length is used. For GCM AES and OCB AES the default is
+12 (i.e. 96 bits). For OCB mode the maximum is 15.

 
 

-Sets the GCM IV length: this call can only be made before specifying an IV. If
-not called a default IV length is used (96 bits for AES).
- 
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, taglen, tag);
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, taglen, tag);

 
 Writes B<taglen> bytes of the tag value to the buffer indicated by B<tag>.
 This call can only be made when encrypting data and B<after> all data has been
 
 Writes B<taglen> bytes of the tag value to the buffer indicated by B<tag>.
 This call can only be made when encrypting data and B<after> all data has been

-processed (e.g. after an EVP_EncryptFinal() call).
+processed (e.g. after an EVP_EncryptFinal() call). For OCB mode the taglen must
+either be 16 or the value previously set via EVP_CTRL_OCB_SET_TAGLEN.

 
 

- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, taglen, tag);
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag);

 
 Sets the expected tag to B<taglen> bytes from B<tag>. This call is only legal
 when decrypting data and must be made B<before> any data is processed (e.g.
 
 Sets the expected tag to B<taglen> bytes from B<tag>. This call is only legal
 when decrypting data and must be made B<before> any data is processed (e.g.

-before any EVP_DecryptUpdate() call). 
+before any EVP_DecryptUpdate() call). For OCB mode the taglen must
+either be 16 or the value previously set via EVP_CTRL_AEAD_SET_TAG.
+
+In OCB mode calling this with B<tag> set to NULL sets the tag length. The tag
+length can only be set before specifying an IV. If not called a default tag
+length is used. For OCB AES the default is 16 (i.e. 128 bits). This is also the
+maximum tag length for OCB.

 
 See L<EXAMPLES> below for an example of the use of GCM mode.
 
 =head1 CCM Mode
 
 
 See L<EXAMPLES> below for an example of the use of GCM mode.
 
 =head1 CCM Mode
 

-The behaviour of CCM mode ciphers is similar to CCM mode but with a few
+The behaviour of CCM mode ciphers is similar to GCM mode but with a few

 additional requirements and different ctrl values.
 
 additional requirements and different ctrl values.
 

-Like GCM mode any additional authenticated data (AAD) is passed by calling
-EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() with the output 
+Like GCM and OCB modes any additional authenticated data (AAD) is passed by calling
+EVP_CipherUpdate(), EVP_EncryptUpdate() or EVP_DecryptUpdate() with the output

 parameter B<out> set to B<NULL>. Additionally the total plaintext or ciphertext
 length B<MUST> be passed to EVP_CipherUpdate(), EVP_EncryptUpdate() or
 parameter B<out> set to B<NULL>. Additionally the total plaintext or ciphertext
 length B<MUST> be passed to EVP_CipherUpdate(), EVP_EncryptUpdate() or

-EVP_DecryptUpdate() with the output and input parameters (B<in> and B<out>) 
+EVP_DecryptUpdate() with the output and input parameters (B<in> and B<out>)

 set to B<NULL> and the length passed in the B<inl> parameter.
 
 The following ctrls are supported in CCM mode:
 set to B<NULL> and the length passed in the B<inl> parameter.
 
 The following ctrls are supported in CCM mode:

- 
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_TAG, taglen, tag);
+
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, taglen, tag);

 
 This call is made to set the expected B<CCM> tag value when decrypting or
 the length of the tag (with the B<tag> parameter set to NULL) when encrypting.
 
 This call is made to set the expected B<CCM> tag value when decrypting or
 the length of the tag (with the B<tag> parameter set to NULL) when encrypting.


@@ -422,7 +453,7 @@ used (12 for AES).
 
 Sets the CCM B<L> value. If not set a default is used (8 for AES).
 
 
 Sets the CCM B<L> value. If not set a default is used (8 for AES).
 

- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_CCM_SET_IVLEN, ivlen, NULL);
+ EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL);

 
 Sets the CCM nonce (IV) length: this call can only be made before specifying
 an nonce value. The nonce length is given by B<15 - L> so it is 7 by default
 
 Sets the CCM nonce (IV) length: this call can only be made before specifying
 an nonce value. The nonce length is given by B<15 - L> so it is 7 by default


@@ -434,9 +465,12 @@ for AES.
 
 Where possible the B<EVP> interface to symmetric ciphers should be used in
 preference to the low level interfaces. This is because the code then becomes
 
 Where possible the B<EVP> interface to symmetric ciphers should be used in
 preference to the low level interfaces. This is because the code then becomes

-transparent to the cipher used and much more flexible.
+transparent to the cipher used and much more flexible. Additionally, the
+B<EVP> interface will ensure the use of platform specific cryptographic
+acceleration such as AES-NI (the low level interfaces do not provide the
+guarantee).

 
 

-PKCS padding works by adding B<n> padding bytes of value B<n> to make the total 
+PKCS padding works by adding B<n> padding bytes of value B<n> to make the total

 length of the encrypted data a multiple of the block size. Padding is always
 added so if the data is already a multiple of the block size B<n> will equal
 the block size. For example if the block size is 8 and 11 bytes are to be
 length of the encrypted data a multiple of the block size. Padding is always
 added so if the data is already a multiple of the block size B<n> will equal
 the block size. For example if the block size is 8 and 11 bytes are to be


@@ -466,7 +500,7 @@ a limitation of the current RC5 code rather than the EVP interface.
 
 EVP_MAX_KEY_LENGTH and EVP_MAX_IV_LENGTH only refer to the internal ciphers with
 default key lengths. If custom ciphers exceed these values the results are
 
 EVP_MAX_KEY_LENGTH and EVP_MAX_IV_LENGTH only refer to the internal ciphers with
 default key lengths. If custom ciphers exceed these values the results are

-unpredictable. This is because it has become standard practice to define a 
+unpredictable. This is because it has become standard practice to define a

 generic key as a fixed unsigned char array containing EVP_MAX_KEY_LENGTH bytes.
 
 The ASN1 code is incomplete (and sometimes inaccurate) it has only been tested
 generic key as a fixed unsigned char array containing EVP_MAX_KEY_LENGTH bytes.
 
 The ASN1 code is incomplete (and sometimes inaccurate) it has only been tested


@@ -474,27 +508,7 @@ for certain common S/MIME ciphers (RC2, DES, triple DES) in CBC mode.
 
 =head1 EXAMPLES
 
 
 =head1 EXAMPLES
 

-Get the number of rounds used in RC5:
-
- int nrounds;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC5_ROUNDS, 0, &nrounds);
-
-Get the RC2 effective key length:
-
- int key_bits;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GET_RC2_KEY_BITS, 0, &key_bits);
-
-Set the number of rounds used in RC5:
-
- int nrounds;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC5_ROUNDS, nrounds, NULL);
-
-Set the effective key length used in RC2:
-
- int key_bits;
- EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC2_KEY_BITS, key_bits, NULL);
-
-Encrypt a string using blowfish:
+Encrypt a string using IDEA:

 
  int do_crypt(char *outfile)
        {
 
  int do_crypt(char *outfile)
        {


@@ -508,8 +522,9 @@ Encrypt a string using blowfish:
        char intext[] = "Some Crypto Text";
        EVP_CIPHER_CTX ctx;
        FILE *out;
        char intext[] = "Some Crypto Text";
        EVP_CIPHER_CTX ctx;
        FILE *out;

+

        EVP_CIPHER_CTX_init(&ctx);
        EVP_CIPHER_CTX_init(&ctx);

-       EVP_EncryptInit_ex(&ctx, EVP_bf_cbc(), NULL, key, iv);
+       EVP_EncryptInit_ex(&ctx, EVP_idea_cbc(), NULL, key, iv);

 
        if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext)))
                {
 
        if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext)))
                {


@@ -538,31 +553,37 @@ Encrypt a string using blowfish:
        }
 
 The ciphertext from the above example can be decrypted using the B<openssl>
        }
 
 The ciphertext from the above example can be decrypted using the B<openssl>

-utility with the command line:
- 
- S<openssl bf -in cipher.bin -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 -d>
+utility with the command line (shown on two lines for clarity):
+
+ openssl idea -d <filename
+          -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708

 
 

-General encryption, decryption function example using FILE I/O and RC2 with an
-80 bit key:
+General encryption and decryption function example using FILE I/O and AES128
+with a 128-bit key:

 
  int do_crypt(FILE *in, FILE *out, int do_encrypt)
        {
        /* Allow enough space in output buffer for additional block */
 
  int do_crypt(FILE *in, FILE *out, int do_encrypt)
        {
        /* Allow enough space in output buffer for additional block */

-       inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];
+       unsigned char inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH];

        int inlen, outlen;
        int inlen, outlen;

+       EVP_CIPHER_CTX ctx;

        /* Bogus key and IV: we'd normally set these from
         * another source.
         */
        /* Bogus key and IV: we'd normally set these from
         * another source.
         */

-       unsigned char key[] = "0123456789";
-       unsigned char iv[] = "12345678";
-       /* Don't set key or IV because we will modify the parameters */
+       unsigned char key[] = "0123456789abcdeF";
+       unsigned char iv[] = "1234567887654321";
+
+       /* Don't set key or IV right away; we want to check lengths */

        EVP_CIPHER_CTX_init(&ctx);
        EVP_CIPHER_CTX_init(&ctx);

-       EVP_CipherInit_ex(&ctx, EVP_rc2(), NULL, NULL, NULL, do_encrypt);
-       EVP_CIPHER_CTX_set_key_length(&ctx, 10);
-       /* We finished modifying parameters so now we can set key and IV */
+       EVP_CipherInit_ex(&ctx, EVP_aes_128_cbc(), NULL, NULL, NULL,
+               do_encrypt);
+       OPENSSL_assert(EVP_CIPHER_CTX_key_length(&ctx) == 16);
+       OPENSSL_assert(EVP_CIPHER_CTX_iv_length(&ctx) == 16);
+
+       /* Now we can set key and IV */

        EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, do_encrypt);
 
        EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, do_encrypt);
 

-       for(;;) 
+       for(;;)

                {
                inlen = fread(inbuf, 1, 1024, in);
                if(inlen <= 0) break;
                {
                inlen = fread(inbuf, 1, 1024, in);
                if(inlen <= 0) break;


@@ -598,4 +619,8 @@ EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex(),
 EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in
 OpenSSL 0.9.7.
 
 EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in
 OpenSSL 0.9.7.
 

+IDEA appeared in OpenSSL 0.9.7 but was often disabled due to
+patent concerns; the last patents expired in 2012.
+
+Support for OCB mode was added in OpenSSL 1.1.0

 =cut
 =cut